HD 224693 is a

star A star is an astronomical object comprising a luminous spheroid of plasma (physics), plasma held together by its gravity. The List of nearest stars and brown dwarfs, nearest star to Earth is the Sun. Many other stars are visible to the naked ...

in the

equatorial Equatorial may refer to something related to: *Earth's equator **the tropics, the Earth's equatorial region **tropical climate *the Celestial equator ** equatorial orbit **equatorial coordinate system ** equatorial mount, of telescopes * equatorial ...

constellation A constellation is an area on the celestial sphere in which a group of visible stars forms Asterism (astronomy), a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object. The origins of the e ...

of Cetus, and is positioned near the western constellation border with

Aquarius Aquarius may refer to: Astrology * Aquarius (astrology), an astrological sign * Age of Aquarius, a time period in the cycle of astrological ages Astronomy * Aquarius (constellation) * Aquarius in Chinese astronomy Arts and entertainment ...

. It can be viewed with a small telescope but is too faint to be seen with the naked eye, having an apparent visual magnitude of 8.23. Based on

parallax Parallax is a displacement or difference in the apparent position of an object viewed along two different lines of sight and is measured by the angle or semi-angle of inclination between those two lines. Due to foreshortening, nearby objects ...

measurements, the object is located at a distance of approximately 306

light year A light-year, alternatively spelled light year, is a large unit of length used to express astronomical distances and is equivalent to about 9.46 trillion kilometers (), or 5.88 trillion miles ().One trillion here is taken to be 1012 ...

s from the Sun. It is drifting further away with a

radial velocity The radial velocity or line-of-sight velocity, also known as radial speed or range rate, of a target with respect to an observer is the temporal rate of change, rate of change of the distance or Slant range, range between the two points. It is e ...

of 1.5 km/s. The star HD 224693 is named Axólotl. The name was selected in the NameExoWorlds campaign by Mexico, during the 100th anniversary of the

IAU The International Astronomical Union (IAU; french: link=yes, Union astronomique internationale, UAI) is a nongovernmental organisation with the objective of advancing astronomy in all aspects, including promoting astronomical research, outreach ...

. Axólotl means water animal in the native

Nahuatl language Nahuatl (; ), Aztec, or Mexicano is a language or, by some definitions, a group of languages of the Uto-Aztecan languages, Uto-Aztecan language family. Varieties of Nahuatl are spoken by about Nahuas, Nahua peoples, most of whom live mainly in ...

, which is an amphibious species from the basin of Mexico. This is an ordinary

G-type main-sequence star A G-type main-sequence star (Spectral type: G-V), also often, and imprecisely called a yellow dwarf, or G star, is a main-sequence star (luminosity class V) of spectral type G. Such a star has about 0.9 to 1.1 solar masses and an effective temp ...

with a

stellar classification In astronomy, stellar classification is the classification of stars based on their stellar spectrum, spectral characteristics. Electromagnetic radiation from the star is analyzed by splitting it with a Prism (optics), prism or diffraction grati ...

of G2V. However, in 2006, Johnson and associates assigned it a class of G2 IV, suggesting it is instead an evolving subgiant star. It is about three billion years old and chromospherically

quiet Quiet may refer to: * Silence, a relative or total lack of sound In music * The Quiett (born 1985), South Korean rapper * ''Quiet'' (album), a 1996 John Scofield album * "Quiet", a song by Lights, from her album '' The Listening'' (2009) * "Qui ...

, with a

projected rotational velocity Stellar rotation is the angular motion of a star about its axis. The rate of rotation can be measured from the spectrum of the star, or by timing the movements of active features on the surface. The rotation of a star produces an equatorial bulge ...

of 4.2 km/s. The star is metal rich, showing a higher abundance of elements other than hydrogen and helium when compared to the Sun. It has 1.3 times the

mass of the Sun The solar mass () is a standard unit of mass in astronomy, equal to approximately . It is often used to indicate the masses of other stars, as well as stellar clusters, nebulae, galaxies and black holes. It is approximately equal to the mass ...

and 1.8 times the Sun's radius. The star is radiating 3.78 times the luminosity of the Sun from its

photosphere The photosphere is a star's outer shell from which light is radiated. The term itself is derived from Ancient Greek roots, φῶς, φωτός/''phos, photos'' meaning "light" and σφαῖρα/''sphaira'' meaning "sphere", in reference to it ...

at an

effective temperature The effective temperature of a body such as a star or planet is the temperature of a black body that would emit the same total amount of electromagnetic radiation. Effective temperature is often used as an estimate of a body's surface temperature ...

of 5,971 K. In 2006, an extrasolar planet was discovered orbiting HD 224693 by the

Keck telescope The W. M. Keck Observatory is an astronomical observatory with two telescopes at an elevation of 4,145 meters (13,600 ft) near the summit of Mauna Kea in the U.S. state In the United States, a state is a constituent political entit ...

using

measurements. A preliminary search for transits using photometric data from

Fairborn Observatory Mount Hopkins is a peak of the Santa Rita Mountains range, in Santa Cruz County, southern Arizona. The peak was named after Gilbert Hopkins, who was killed nearby during the Battle of Fort Buchanan in 1865. It is in the Coronado National For ...

was inconclusive because data around the predicted time of transit was too sparse to rule out possible transits. This exoplanet was named Xolotl, as the Aztec god of fire and lightning.

References

External links

* {{DEFAULTSORT:HD 224693 G-type main-sequence stars G-type subgiants Planetary systems with one confirmed planet Cetus (constellation) Durchmusterung objects 224693 118319

See also

References

External links